In general, electronic devices, such as computers and servers, are equipped with multiple data transmission ports, including USB (Universal Serial Bus), Mini DisplayPort, and HDMI (High Definition Multimedia Interface). The data transmission ports are required for data transmission, because they admit and hold the connectors of cables connected to external electronic devices, and access-oriented devices, such as USB flash drives and USB hard disks.
To ensure data security or facilitate management, unauthorized persons are prohibited from accessing electronic devices, such as computers and servers in plenty of places, such as public spaces and offices. The related prior art entails filling the data transmission ports of electronic devices, such as computers and servers, with fillers, such as a hot glue, or adhering adhesives, such as an adhesive tape, to the data transmission ports, so as to close the data transmission ports. Although the aforesaid prior art is simple, it has a drawback, that is, difficulty in removing the fillers, such as a hot glue, and adhesives, such as an adhesive tape, from the otherwise closed data transmission ports.